powerpc: convert to generic helpers for IPI function calls

This converts ppc to use the new helpers for smp_call_function() and
friends, and adds support for smp_call_function_single().

ppc loses the timeout functionality of smp_call_function_mask() with
this change, as the generic code does not provide that.

Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

include/asm-powerpc/smp.h

@@ -67,10 +67,7 @@ DECLARE_PER_CPU(cpumask_t, cpu_sibling_map);
  * in /proc/interrupts will be wrong!!! --Troy */
 #define PPC_MSG_CALL_FUNCTION   0
 #define PPC_MSG_RESCHEDULE      1
-/* This is unused now */
-#if 0
-#define PPC_MSG_MIGRATE_TASK    2
-#endif
+#define PPC_MSG_CALL_FUNC_SINGLE	2
 #define PPC_MSG_DEBUGGER_BREAK  3
 
 void smp_init_iSeries(void);
@@ -117,6 +114,9 @@ extern void smp_generic_take_timebase(void);
 
 extern struct smp_ops_t *smp_ops;
 
+extern void arch_send_call_function_single_ipi(int cpu);
+extern void arch_send_call_function_ipi(cpumask_t mask);
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* __KERNEL__ */